Eighty years ago, the September 1936 issue of Radio Craft magazine carried the plans for this “talking briefcase” receiver.

The authors of the project article, Hugo Gernsback and J.T. Bernsley, noted that the set’s novelty and usefulness had been well attested to by hundreds of admiring and envious comments made by spectators who saw the set operating on the streets of Brooklyn and Manhattan. They noted that while there had been other portables, nobody had really seen a true pedestrian set until this one came along.

The set was a four tube TRF, with a total weight under 11 pounds, including briefcase, chassis, and batteries. A modern magnetic speaker with alnico magnet provided excellent tone quality. A TRF circuit was chosen due to simplicity of construction, as well as the fact that a serviceman’s signal generator wouldn’t be required to align the set, as would be the case with a superhet. A 3-gang variable condenser tuned all of the stages simultaneously.

The set featured two 1A4 tubes as RF amplifiers, a 32 detector, and type 95D serving as AF amp. No antenna or ground was required. Wire was wrapped around the handle of the briefcase, and when carried, the owner’s body was capacitively coupled and served as the antenna. For use when not walking, a 10-15 foot section of wire could be tossed on the floor to serve as antenna.

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